TECHNICAL FIELD
[0001] This disclosure generally relates to fuselage structures, especially those formed
of composites, and deals more particularly with a fuselage having a multifunctional
crown.
BACKGROUND
[0002] Polymer-based composites may be selected for use in fabricating aircraft structures
because of their favorable strength-to-weight ratio. Current designs for aircraft
fuselage may employ a number of composite components, including sandwich panels, frames
and stiffeners, to name only a few. The assembly of these composite components during
the fabrication process may be time consuming and labor intensive, consequently, it
is desirable to integrate these components where possible, in order to reduce assembly
time and/or labor as well as aircraft weight.
[0003] Assembly time/labor as well as aircraft weight may also be reduced by simplifying
onboard aircraft subsystems such as environmental control systems (ECS), electrical
wiring and communication systems. The problem of reducing the number of composite
structural components and simplifying onboard subsystems is complicated by the fact
that larger commercial and military aircraft fuselages are fabricated in sections
that must be joined together during the production process.
[0004] Accordingly, there is a need for a composite aircraft fuselage having a reduced number
of components requiring assembly while integrating at least portions of aircraft subsystems
in order to reduce costs and aircraft weight. There is also a need for a method of
fabricating a composite aircraft fuselage which allows integration of subsystems during
assembly of the fuselage sections while increasing production rates.
SUMMARY
[0005] The disclosed embodiments provide a composite fuselage structure having a multifunctional
crown that integrates one or more aircraft subsystems, thereby reducing the number
of components requiring assembly. The multifunctional crown provides a unitized design
exhibiting improved strength and impact resistance to object strikes, such as hail.
Integration of aircraft subsystems into the multi-functional crown may result in improvements
in manufacturing and structural efficiencies, energy transport and remote structural
health and moisture ingress monitoring. The multifunctional fuselage crown provides
shielded pathways for transmission of RF (radio frequency) through the aircraft. These
shielded pathways may be used to supply RF energy to structural health monitoring
sensors and/or for data communications. The pathways are formed by one or more waveguide
cavities integrated into the crown which provides shielding from the ambient environment,
which may reduce disruptions in communication links.
[0006] Wireless communication through the integrated waveguide cavity may result in higher
data rates, longer range, larger capacity and lower operating power. The use of the
multi-function crown as a waveguide cavity may allow nondestructive evaluation (NDE)
of remote areas of a unitized aircraft structure, thereby possibly obviating the need
for disassembling parts of the aircraft in order to perform NDE or structural health
monitoring.
[0007] According to one disclosed embodiment, a fuselage structure comprises a fuselage
body having an inner surface and framework for stiffening the body. The framework
includes at least one frame member attached to the inner surface and having a duct
therein for routing a utility through the body. The utility may include one or more
of an environmental control system, electrical wiring, a wireless communication system,
a wireless electrical power delivery system and a moisture monitoring system. The
duct forms an electromagnetic energy waveguide cavity allowing wireless data transmission
of electromagnetic signals through the frame member. The fuselage body includes an
upper portion having a crown, a cabin beneath the crown and a lower portion. The framework
includes a plurality of arched frame members attached to the upper portion of the
fuselage body and extending transversely across the crown. At least certain of the
frame members include an integral cavity therein extending downwardly from the crown
toward the cabin. The fuselage structure may further comprise an air supply duct extending
longitudinally through the body in the area of the crown and coupled with the frame
member cavities. The air supply duct may be integrated into each of the arched frame
members and form a portion of the framework.
[0008] According to another disclosed embodiment, a fuselage structure comprises a body
including an inner surface defining a cabin, and a plurality of circumferentially
extending composite frame members around the cabin for reinforcing the body. Each
of the frame members is attached to the inner surface of the fuselage body, and includes
a utility service distribution duct therein for distributing a utility service to
the cabin. The body may comprise composite panels, including an upper portion having
a crown and a lower portion joined with the upper portion. Each of the frame members
is joined to the panels in the upper portion of the body and spans the crown. The
fuselage structure may further comprise a utility supply duct extending longitudinally
through the body and coupled with the distribution ducts in the frame members. The
utility supply duct may be integral with the frame members and is disposed between
the crown and the cabin.
[0009] According to a further embodiment, a fuselage structure comprises a body having a
crown and a frame extending longitudinally through the body for stiffening the body
in the area of the crown. The frame includes at least one duct therein for routing
a utility through the body.
[0010] According to a further embodiment, a method is provided of manufacturing aircraft
fuselages. The method comprises laying up a composite structure over a tool and separating
the composite structure into first and second fuselage skins. The method further includes
forming two fuselage portions respectively using the first and second skins.
CLAUSES SETTING OUT FURTHER ASPECTS AND EMBODIMENTS
[0011]
- 1. A fuselage structure, comprising: a fuselage body including an inner surface; and
structural framework for stiffening the body, the structural framework including at
least one frame member attached to the inner surface and having a duct therein for
routing a utility through the body.
- 2. The fuselage structure of clause 1, wherein the utility includes at least one of:
an environmental control system, electrical wiring, a wireless communication system,
a wireless electrical power delivery system, and a moisture monitoring system.
- 3. The fuselage structure of clause 1, wherein: the duct forms an electromagnetic
energy waveguide cavity, and the utility includes a wireless data transmission system
transmitting electromagnetic signals through the waveguide cavity.
- 4. The fuselage structure of clause 1, wherein: the fuselage body includes an upper
portion having a crown, a cabin beneath the crown, and a lower portion, and the structural
framework includes a plurality of arched frame members attached to the inner surface
of the upper portion of the fuselage body and extending transversely across the crown,
wherein at least certain of the frame members include an integral cavity therein extending
downwardly from the crown toward the cabin.
- 5. The fuselage structure of clause 4, further comprising: an air supply duct extending
longitudinally through the body in the area of the crown and coupled with the frame
member cavities.
- 6. The fuselage structure of clause 5, wherein the air supply duct is integrated into
each of the arched frame members and forms a portion of the structural framework.
- 7. The fuselage structure of clause 1, wherein the body and the structural framework
are formed of composite materials.
- 8. The fuselage structure of clause 1, wherein the structural framework includes a
plurality of ached frame members attached to the fuselage body and extending transversely
across the crown, wherein each of the arched frame members is filed with a structural
foam and includes a conduit surrounded and supported by the foam.
- 9. The fuselage structure of clause 1, wherein: the fuselage body includes an upper
portion having sides and a crown formed of a composite panels, the panels including
a core sandwiched between inner and outer facesheets, wherein the core has increased
stiffness in the area of the crown.
- 10. A fuselage structure, comprising: a body defining a cabin; and a plurality of
circumferentially extending composite frame members around the cabin for reinforcing
the body, each of the frame members being attached to the body and having a utility
distribution duct therein for distributing a utility service to the cabin.
- 11. The fuselage structure of clause 10, wherein: the body is formed of composite
panels, the body including an upper portion having a crown, and a lower portion joined
to the upper portion, wherein each of the frame members is connected to the panels
in the upper portion of the body and spans the crown.
- 12. The fuselage structure of clause 11, further comprising: a utility supply duct
extending longitudinally through the body and coupled with the distribution ducts
in the frame members.
- 13. The fuselage structure of clause 12, wherein the utility supply duct forms a backbone
frame and is integral with the frame members.
- 14. The fuselage structure of clause 12, wherein the utility supply duct is disposed
between the crown and the cabin.
- 15. The fuselage structure of clause 12, wherein the utility is one of: environmental
control, wireless communications, and electrical control.
- 16. The fuselage structure of clause 12, wherein:
each of the frame members is filled with a structural foam, and the ducts extend through
the structural foam.
- 17. A fuselage structure, comprising: a body having a crown; and a frame extending
longitudinally through the body for stiffening the body in the area of the crown,
the frame including at least one duct therein for routing a utility through the body.
- 18. The fuselage of clause 17, further comprising: a plurality of longitudinally spaced,
arched frame members attached to the body for stiffening the body, at least certain
of the arched frame members including ducts therein coupled with the duct in the longitudinally
extending frame.
- 19. The fuselage of clause 17, wherein: each of the arched frame members and the longitudinally
extending frame member are formed of composite materials, and the arched frame members
and the longitudinally extending frame member are formed integral with each other.
- 20. The fuselage of clause 17, wherein the utility includes at least one of: an environmental
control system, electrical wiring, a wireless communication system, a wireless electrical
power delivery system, and a moisture monitoring system.
- 21. The fuselage of clause 17, wherein the body and the longitudinally extending frame
are each formed of a polymer-based composite.
- 22. A method of manufacturing aircraft fuselages, comprising: laying up a composite
structure over a tool; separating the composite structure into first and second outer
fuselage skins; and forming two fuselage portions respectively using the first and
second outer skins.
- 23. The method of clause 22, wherein forming two fuselage portions respectively using
the first and second outer skins includes: placing the first and second outer skins
respectively first and second outer mold line tools, placing a core over each of the
first and second pouter skins, and laying up a composite inner skin over each of the
molds.
- 24. The method of clause 23, wherein forming two fuselage portions respectively using
the first and second outer skins further includes: laying up arched composite frame
members over each of the inner skins, laying up a longitudinally extending frame over
each of the inner skins integrated with the arched frame members, and curing each
of the fuselage portions.
- 25. A aircraft fuselage, comprising: an outer body formed of composite sandwich panels
including a core sandwiched between an inner and an outer skin, the body including
an upper portion having a crown and a lower portion joined to the upper portion along
a longitudinally extending joint, wherein the core has a section of increased strength
in the area of the crown; a plurality of longitudinally spaced composite arched frame
members joined to the inner skin of the panels in the upper portion of the body for
stiffening the body in the area of the crown, at least certain of the arched frame
members including a duct therein for distributing air downwardly from the area of
the crown; and a longitudinally extending composite backbone frame formed integral
with the arched frame members and attached to the inner skin in the area of the crown,
the backbone frame including an internal duct coupled with the ducts in the arched
frame members.
- 26. A method of manufacturing aircraft fuselages, comprising: laying up a composite
structure over a double mandrel; cutting the composite structure into first and second
outer fuselage skins; placing the first and second outer skins respectively first
and second outer mold line tools; placing a core over each of the first and second
outer skins; laying up a composite inner skin over each of the cores; laying up arched
composite frame members over each of the inner skins; laying up a longitudinally extending
composite frame over each of the inner skins integrated with the arched frame members
to form two upper fuselage portions; curing each of the upper fuselage portions; and
joining two lower fuselage portions respectively to the upper fuselage portions to
for two fuselage sections.
BRIEF DESCRIPTION OF THE ILLUSTRATIONS
[0012]
FIG. 1 is an illustration of a perspective view of an aircraft fuselage section having
a multifunctional crown.
FIG. 2 is an illustration of a view similar to FIG. 1 but with the outer body panels
having been removed to reveal the framework.
FIG. 3 is an illustration of a perspective view of an upper portion of the fuselage
section shown in FIG. 1.
FIG. 4 is an illustration of a sectional view taken along the line 4-4 in FIG. 3.
FIG. 5 is an illustration of a perspective view similar to FIG. 3 but showing an alternate
form of body panel construction.
FIG. 6 is an illustration of the area designated as "6" in FIG. 5.
FIG. 7 is an illustration similar to FIG. 3 but showing a further embodiment of the
body panel construction.
FIG. 8 is an illustration of the area designated as "8" in FIG. 7.
FIG. 9 is an illustration of a perspective view similar to FIG. 3 but showing another
embodiment of the body panel construction.
FIG. 10 is an illustration of the area designated as "10" in FIG. 9.
FIG. 11 is an illustration of a perspective view of an upper body portion having a
crown reinforced by internal stiffeners.
FIG. 12 is an illustration of the area designated as "12" in FIG. 11.
FIG. 13 is an illustration of a perspective view of another embodiment of the upper
portion of a fuselage section employing a multifunctional crown.
FIG. 14 is an illustration of a perspective sectional view taken along the line 14-14
in FIG. 13.
FIG. 15 is an illustration of an end view of an alternate form of the multifunctional
crown.
FIG. 16 is an illustration of a perspective view of an upper portion of the fuselage
section employing another form of the multifunctional crown.
FIG. 17 is an illustration of a perspective view of the multifunctional crown shown
in FIG. 16, parts being broken away in section to review the connections between the
supply duct and the distribution ducts.
FIG. 18 is an illustration of a functional block diagram of a wireless transmission
system used in fuselage structures employing the multifunctional crown.
FIG. 19 is an illustration of perspective views of components, showing the steps of
a method of making fuselage structures.
FIG. 20 is an illustration of a flow diagram of the manufacturing method illustrated
in FIG. 19.
FIG. 21 is a flow diagram of aircraft production and service methodology.
FIG. 22 is a block diagram of an aircraft.
DETAILED DESCRIPTION
[0013] Referring first to FIGS. 1 and 2, a barrel-shaped fuselage section 30 comprises upper
and lower fuselage portions 32, 34 respectively connected together along a longitudinally
extending joint 36 which integrates the two portions 32, 34 with a unitized floor
42. During the fabrication of an aircraft (not shown), two or more of the barrel-shaped
fuselage sections 30 may be joined together end-to-end to form a complete fuselage
(not shown). The upper fuselage portion 32 includes sides 38 and a crown 40. As will
be discussed below in more detail, each of the fuselage portions 32, 34 may be formed
of composite sandwich panels (not shown) joined together to form an outer body 25
that includes an inner skin 56 defining an inner surface of the body 25 and an outer
skin 64. In other embodiments, the body 25 may be formed of a single skin 56, rather
than composite sandwich panels. Although the illustrated fuselage section 30 has a
generally circular cross sectional shape, a variety of other cross-sectional shapes
and combinations of shapes are possible, including but not limited to oval and other
shapes.
[0014] The floor 42 is supported by one or more frames (not shown) or other supports (not
shown) forming part of the fuselage section 30. In the illustrated embodiment, fuselage
section 30 includes a single floor 42 extending across the fuselage section 30 at
the level of the joint 36 to define an upper cabin 44, however, more than one floor
42 is possible. The upper portion 32 of the fuselage section 30 is reinforced by structural
framework 46 comprising a plurality of longitudinally spaced, arched structural frame
members 48 which are joined to the inner surface of the body 25 defined by the inner
skin 56. Frame members 48 extend circumferentially around substantially the entire
perimeter of the upper fuselage portion 32, but may have extremities 50 that taper
in cross sectional area in the area of the sides 38.
[0015] Depending upon the particular application and aircraft geometry, the structural framework
46 may include additional arched frame members 48a around openings such as the doorway
54 in the fuselage section 30. Depending upon structural loads of the application,
the arch frame members 48 may vary in cross-sectional dimensions, overall height and
length, and spacing from each other. Although not shown in FIGS. 1 and 2, the structural
framework 46 may include a longitudinally extending backbone frame member in the area
of the crown 40 which structurally joins the frame members 40 together and provides
the fuselage section 30 with rigidity in the longitudinal direction of the aircraft.
Additional details of a suitable fuselage section 30 of the type described above may
be found in
US Patent 7,735,779 issued on June 15, 2010, the entire contents of which are incorporated by reference herein.
[0016] FIGS. 3 and 4 illustrate one embodiment of the upper fuselage portion 32 having an
outer body 25 formed of a solid, polymer based laminate 35 such as, for example and
without limitation, carbon fiber reinforced epoxy. The sides 38 and the crown 40 are
reinforced by composite, arched frame members 48. Each of the frame members 48 may
have a cross section suited for the application. In the illustrated example, each
of the frame members 48 is hat-shaped in cross section and includes outer flanges
58 that are secured to the inner skin 56 through co-curing, bonding and/or fasteners
(not shown). For simplicity, the flanges 58 are omitted from FIGS. 3, 5, 7, 9, 11,
13, 16 and 17. Frames members 48 may be filled with a suitable structural foam 60.
[0017] FIGS. 5 and 6 illustrate another embodiment of the upper fuselage portion 32 in which
the outer body 25 is formed of a sandwich panel construction, comprising a core 55
sandwiched between inner and outer face sheets 56, 64 respectively. The core 55 may
comprise any suitable material and geometry such as, without limitation, flutes (not
shown) or a honeycomb (not shown). In the illustrated example, the core 55 includes
a relatively high density section 66 in the area of the crown 40, at a lower density
section 62 in the sides 38. The high density core section 66 provides the crown 40
with additional strength and rigidity, as well as impact resistance to objects such
as hail striking the top (crown 40) of the aircraft, while the aircraft is on or near
the ground. The high and low density sections 66, 62 of the core 55 may be connected
together along a scarf joint 68, although other types of joints are possible, including
but not limited to a lap joint, a step-lap joint, and a butt joint.
[0018] FIGS. 7 and 8 illustrate a further embodiment of the upper fuselage portion 32 in
which the body 25 comprises a solid laminate 70 in the area of the crown 40 and a
composite sandwich in the sides 38, comprising a relatively medium density core 62
sandwiched between the inner and outer face sheets 56, 64. The composite sandwich
sides 38 transitions to the solid laminate 70 along a double scarf joint 68 formed
by a ramp-down 69 in the core 62; other type of joints may be possible.
[0019] FIGS. 9 and 10 illustrate another embodiment of the upper fuselage portion 32 which
is similar to the embodiment shown in FIGS. 7 and 8, except that the solid laminate
70 in the crown 40 is provided with longitudinally extending, high density integrated
stiffeners 72 which provide the body 25 in the area of the crown 40 with additional
longitudinal stiffness and stability, if required. In this example, the stiffeners
72 are circumferentially spaced from each other and are sandwiched between the inner
and outer face sheets 56, 64 respectively. While FIG. 10 shows the stiffeners 72 as
being located substantially in the middle between the inner and outer skins 56, 64,
the stiffeners 72 may be located closer to the inner skin 56 or closer to the outer
skin 64, if desired. In still other embodiments, such as that shown in FIG. 11, the
stiffeners 72 may be located on the inner skin 56.
[0020] FIGS. 11 and 12 illustrate another technique for reinforcing and stiffening the crown
40 of the upper fuselage portion 32. In this embodiment, circumferentially spaced,
longitudinally extending composite stiffeners 74 are attached to the inner skin 56
in the area of the crown 40. In the illustrated example, the stiffeners 74 have a
J-shaped cross section, however a variety of other cross sectional shapes are possible.
Stiffeners 74 may be attached to the inner skin 56 by bonding or other techniques.
The stiffeners 74 may also provide a means of attaching equipment (not shown) or subsystems
(not shown) to the body 25.
[0021] FIG. 13 illustrates another embodiment of the upper fuselage portion 32 wherein the
crown 40 is provided with a longitudinally extending, centrally located backbone frame
82. The backbone frame 82 interconnects and may be integrally formed with the arched
frame members 48 to form internal structural framework 46 that is substantially unitized
and stiffened in the area of the crown 40. In this example, the backbone frame 82
includes a pair of integrally formed, longitudinally extending internal ducts 78 which
are separated from each other by a central partition 80. The backbone frame 82 may
comprise a composite laminate that is laid up and co-cured along with arched frame
members 48 during a fabrication process that will be described below in more detail.
In the illustrated embodiment, ducts 78 form port and starboard air supply ducts that
carry air from a source (not shown) longitudinally through the aircraft along the
crown 40.
[0022] As shown in FIG. 14, one or more of the arched frame members 48 may include a distribution
duct 84 that is held in place by a structural foam 60 filling the frame member 48.
Each of the distribution ducts 84 is connected with one of the supply ducts 78 and
functions to direct air supplied at 82 outward and downward as shown by the arrows
76 into the cabin 44. As will be discussed below in more detail, one or more ducts
78 formed by the backbone frame 82 may be employed to allow other utilities to be
directed through the aircraft along the crown 40, including but not limited to other
types of environmental control systems, wireless communications, hard electrical wiring,
wireless power delivery and various systems for monitoring the structural health of
the aircraft, including moisture monitoring systems.
[0023] FIG. 15 illustrates the provision of a tray 88 attached to the lower part of the
backbone frame 82 which may be used to support and route onboard subsystems such as,
without limitation, electrical wiring, longitudinally through the aircraft.
[0024] While FIG. 13 illustrates ducts 78 formed by the integrated backbone frame 82, it
may be possible to distribute utility services through the frame members 48 using
a semi-integrated central supply conduit 85 shown in FIGS. 16 and 17, which is located
along the crown 40. In this example, the conduit 85 is generally oval in cross section,
however other cross sectional shapes are possible. The conduit 85 is centrally located
beneath the crown 40 and extends longitudinally through the upper fuselage portion
32. Each of the frame members 48 may include a recessed portion 96 having a shape
substantially matching that of the conduit 85 in order to recess the conduit 85 into
the frame members 48 so that the conduit 85 does not extend downwardly into the cabin
44 any more than is necessary. The conduit 85 may be formed of any suitable, relatively
rigid material, including but not limited to composites.
[0025] The conduit 85 may be attached to either or both the arched frame members 48 and
body 25 using fasteners, bonding techniques or interlocking mechanical mechanisms
(all not shown). As seen in FIG. 17, the conduit 85 includes an internal cavity 90
through which a utility may be routed. In the illustrated example, the conduit 85
is provided with outlet openings 92 that are coupled with inlet openings 94 in the
frame members 48.
[0026] Referring now to FIG. 18, as previously mentioned, the ducts 78, 84 formed in the
structural framework 46 may be used to supply and distribute any of various utilities
through the aircraft. FIG. 18 illustrates the use of the framework ducts 78, 84 as
waveguide cavities used to transmit electromagnetic signals in the form of data or
power through the aircraft. In one example, one or more wireless transceivers 100
positioned at longitudinally spaced locations in the aircraft, may be used to transmit
data or power signals through the waveguide cavity 98 (framework ducts 78, 84). For
example, any of a number of airplane heath monitoring sensors, energy harvesters,
RFID tags, etc. collectively shown at 104, may be monitored at another location in
the aircraft using the wireless transceivers 100 to transmit data signals.
[0027] At least one of the wireless transceivers 100 may be coupled with a suitable onboard
computer 106 which may function to interrogate and/or monitor the devices 104. The
wireless transceivers 100 in combination with the waveguide cavity 98 may be used
to wirelessly transmit power generated by power supply 108 through the aircraft in
order to power one or more of the devices 104. Alternatively, power generated by an
energy harvesting device 104 may be transmitted through the waveguide cavity 98 to
batteries which may form part of the power supply 108.
[0028] The upper fuselage portion 32 having a multifunctional crown 40 may be manufactured
according to a method illustrated in FIGS. 19 and 20. Beginning at 122, composite
material is laid up over a double mandrel 113 using an automatic fiber placement machine
or using other conventional techniques for laying up composite material over a shaped
tool. At 124, the layup 112 is cut and separated into two substantially identical
outer skins 112a, 112b. At 126, the outer inner skins 112a, 112b are placed in a pair
of substantially identical, outer mold line tools 114, 116. Next, at 128, foam cores
118a, 118b are laid up over the outer skins 112a, 112b. At step 130, inner skins 120a,
120b are laid up over the corresponding cores 118a, 118b, using hand placement techniques
or automatic fiber placement equipment (not shown). While the above described method
provides for the substantially simultaneous fabrication of two fuselage portions 32
using a single double mandrel 113, the outer skins 112a, 112b may be laid up over
two separate mandrels (not shown), if desired.
[0029] While the fabrication method shown in FIG. 10 may be carried out by laying prepreg
fiber plies, it may also be possible to fabricate the fuselage body portions 32, or
sections thereof, using dry fiber preforms (not shown) and resin infusion techniques.
For example, and without limitation, the arched frame members 48 and the backbone
frame 82 may be integrally formed together using dry preforms (not shown) that are
placed on the inner skins 120a shown in FIG. 19, and then co-infused with resin.
[0030] At 132, the arched frame members 48 are laid up over the inner skins 120a, 120b thereby
forming two substantially identical body portions 32. At step 133 shown in FIG. 20,
the laid up upper body portions 32 are vacuum bagged, processed and cured resulting
in a co-cured, unitized structure. At 134, the cured body portions 32 are removed
from the outer mold line tools 114, 116. At 134, the cured body portions 32 may be
trimmed, as needed following which the upper body portions 32 may be joined to pre-cured
lower body portions 34 (FIG. 1).
[0031] Referring next to FIGS. 21 and 22, embodiments of the disclosure may be used in the
context of an aircraft manufacturing and service method 140 as shown in FIG. 21 and
an aircraft 142 as shown in FIG. 22. During pre-production, exemplary method 140 may
include specification and design 144 of the aircraft 142 and material procurement
146. During production, component and subassembly manufacturing 148 and system integration
150 of the aircraft 142 takes place. During step 148, the disclosed method and apparatus
may be employed to fabricate composite parts such as fuselage sections which are then
assembled at step 150. Thereafter, the aircraft 142 may go through certification and
delivery 152 in order to be placed in service 154. While in service by a customer,
the aircraft 142 may be scheduled for routine maintenance and service 156 (which may
also include modification, reconfiguration, refurbishment, and so on).
[0032] Each of the processes of method 140 may be performed or carried out by a system integrator,
a third party, and/or an operator (e.g., a customer). For the purposes of this description,
a system integrator may include without limitation any number of aircraft manufacturers
and major-system subcontractors; a third party may include without limitation any
number of vendors, subcontractors, and suppliers; and an operator may be an airline,
leasing company, military entity, service organization, and so on.
[0033] As shown in FIG. 22, the aircraft 142 produced by exemplary method 140 may include
an airframe 158 with a plurality of systems 160 and an interior 162. The disclosed
method and apparatus may be employed to fabricate fuselage sections which form part
of the airframe 158. Examples of high-level systems 150 include one or more of a propulsion
system 164, an electrical system 166, a hydraulic system 168, and an environmental
system 170. Any number of other systems may be included. Although an aerospace example
is shown, the principles of the invention may be applied to other industries, such
as the automotive industry.
[0034] The apparatus embodied herein may be employed during any one or more of the stages
of the production and service method 140. For example, components or subassemblies
corresponding to production process 148 may be fabricated or manufactured in a manner
similar to components or subassemblies produced while the aircraft 142 is in service.
Also, one or more apparatus embodiments may be utilized during the production stages
148 and 150, for example, by substantially expediting assembly of or reducing the
cost of an aircraft 142. Similarly, one or more apparatus embodiments may be utilized
while the aircraft 142 is in service, for example and without limitation, to maintenance
and service 156.
[0035] Although the embodiments of this disclosure have been described with respect to certain
exemplary embodiments, it is to be understood that the specific embodiments are for
purposes of illustration and not limitation, as other variations will occur to those
of skill in the art.
1. A fuselage structure, comprising:
a fuselage body including an inner surface; and
structural framework for stiffening the body, the structural framework including at
least one frame member attached to the inner surface and having a duct therein for
routing a utility through the body.
2. The fuselage structure of claim 1, wherein the utility includes at least one of:
an environmental control system,
electrical wiring,
a wireless communication system,
a wireless electrical power delivery system, and
a moisture monitoring system.
3. The fuselage structure of claim 1, wherein:
the duct forms an electromagnetic energy waveguide cavity, and
the utility includes a wireless data transmission system transmitting electromagnetic
signals through the waveguide cavity.
4. The fuselage structure of claim 1, wherein:
the fuselage body includes an upper portion having a crown, a cabin beneath the crown,
and a lower portion, and
the structural framework includes a plurality of arched frame members attached to
the inner surface of the upper portion of the fuselage body and extending transversely
across the crown, wherein at least certain of the frame members include an integral
cavity therein extending downwardly from the crown toward the cabin.
5. The fuselage structure of claim 4, further comprising:
an air supply duct extending longitudinally through the body in the area of the crown
and coupled with the frame member cavities.
6. The fuselage structure of claim 5, wherein the air supply duct is integrated into
each of the arched frame members and forms a portion of the structural framework.
7. The fuselage structure of claim 1, wherein the body and the structural framework are
formed of composite materials.
8. The fuselage structure of claim 1, wherein the structural framework includes a plurality
of ached frame members attached to the fuselage body and extending transversely across
the crown, wherein each of the arched frame members is filed with a structural foam
and includes a conduit surrounded and supported by the foam.
9. The fuselage structure of claim 1, wherein:
the fuselage body includes an upper portion having sides and a crown formed of a composite
panels, the panels including a core sandwiched between inner and outer facesheets,
wherein the core has increased stiffness in the area of the crown.
10. A method of manufacturing aircraft fuselages, comprising:
laying up a composite structure over a tool;
separating the composite structure into first and second outer fuselage skins; and
forming two fuselage portions respectively using the first and second outer skins.
11. The method of claim 10, wherein forming two fuselage portions respectively using the
first and second outer skins includes:
placing the first and second outer skins respectively first and second outer mold
line tools,
placing a core over each of the first and second pouter skins, and
laying up a composite inner skin over each of the molds.
12. The method of claim 11, wherein forming two fuselage portions respectively using the
first and second outer skins further includes:
laying up arched composite frame members over each of the inner skins,
laying up a longitudinally extending frame over each of the inner skins integrated
with the arched frame members, and
curing each of the fuselage portions.